The Unsung Hero of Battery Production

While breakthroughs in battery-driven products and solutions might grab headlines, a silent hero works diligently behind the scenes to ensure battery preservation and efficiency – the Karl Fischer Titrator.

While Karl Fischer (KF) titration heralds as the champion of battery production quality control, techniques like Loss-on-Drying (LOD) and Thermogravimetric Analysis (TGA) support its main mission of meticulously measuring the water content of battery materials and electrolytes.

Performance degradation:

Water reacts with the electrolyte's conducting salt (like LiPF₆), which breaks down the electrolyte and can initiate the formation of hydrofluoric acid. The resulting hydrogen fluoride (HF) can then attack and corrode the battery materials, reducing performance and potentially hazardous conditions.

Safety hazards:

During normal operation, batteries generate a small amount of heat due to the movement of electrons between the anode and cathode. However, if internal components, such as thermal sensors or protection circuits, fail due to moisture or the breakdown of these components by HF, a dangerous situation called thermal runaway can occur.

Thermal runaway is a hazardous condition that occurs when temperatures in the battery cell escalate uncontrollably, potentially causing a fire or even an explosion. 

Let’s break down how that can happen. The process starts at a seemingly low temperature of 80°C, where the protective layer on the anode (the Solid Electrolyte Interface, or SEI) begins to break down in a reaction that releases heat, triggering the following chain reaction:

• As temperatures climb between 100°C and 120°C, the electrolyte itself starts to decompose, unleashing various gases that can contribute to an impending explosion, such as CO, CO₂, CH₄, C₂H₄, H₂

• The situation becomes even more critical between 120°C and 130°C when the separator component melts, causing an internal short circuit that further accelerates heat generation.

• By the time temperatures reach 150°C, the cathode reacts with the electrolyte, generating oxygen and driving the cell toward complete failure.

• If left unchecked and temperatures surpass 180°C, the reaction becomes self-sustaining. The resulting oxygen produced further feeds the breakdown process, creating a dangerous runaway scenario where temperatures rise rapidly and can lead to a battery fire or explosion.

As you can see, even small traces of water can ignite a disastrous and dangerous situation, provoking the need for meticulous inspection. Enter Karl Fischer titration – our dependable aid in precisely measuring and controlling water content in lithium-ion materials, ensuring minimal moisture reaches the final cell.

• Mitigating Electrolyte Degradation: Controlled water content safeguards against electrolyte breakdown. Maintaining optimal capacity and power delivery translates into enhanced battery performance and extended use cycles between charges.

• Reduced Internal Resistance: Batteries that experience less internal resistance have higher efficiency and overall performance, i.e., your electric vehicle going further on a single charge (quelling range anxiety and supporting sustainability).

• Abating Side Reactions: The combined prowess of KF titration, LOD, and TGA minimizes safety hazards arising from water-induced side reactions, including volatile and dangerous events. This strict approach fosters reliable and safe battery operation for various applications.